chore(web): refactor xtext client

37 files changed, 289 insertions, 2105 deletions

diff --git a/language-web/.eslintrc.ci.js b/language-web/.eslintrc.ci.js
index b4c83bb8..804f66de 100644
--- a/language-web/.eslintrc.ci.js
+++ b/language-web/.eslintrc.ci.js
@@ -28,6 +28,5 @@ module.exports = {
   ignorePatterns: [
     '*.js',
     'build/**/*',
-    'src/main/js/xtext/**/*',
   ],
 };
diff --git a/language-web/build.gradle b/language-web/build.gradle
index 6aaf546b..ea2f1269 100644
--- a/language-web/build.gradle
+++ b/language-web/build.gradle
@@ -47,7 +47,7 @@ def installFrontend = tasks.named('installFrontend')
 
 def generateLezerGrammar = tasks.register('generateLezerGrammar', RunNpmYarn) {
         dependsOn installFrontend
-        inputs.file('src/main/js/editor/problem.grammar')
+        inputs.file('src/main/js/language/problem.grammar')
         inputs.files('package.json', 'yarn.lock')
         outputs.file "${buildDir}/generated/sources/lezer/problem.ts"
         outputs.file "${buildDir}/generated/sources/lezer/problem.terms.ts"
@@ -153,10 +153,6 @@ sonarqube.properties {
                 'src/main/html',
                 'src/main/js',
         ]
-        properties['sonar.exclusions'] += [
-                'src/main/css/xtext/**',
-                'src/main/js/xtext/**',
-        ]
         property 'sonar.nodejs.executable', "${nodeDirectory}/bin/node"
         property 'sonar.eslint.reportPaths', "${buildDir}/eslint.json"
         property 'sonar.css.stylelint.reportPaths', "${buildDir}/stylelint.json"
diff --git a/language-web/package.json b/language-web/package.json
index 016d9dc1..a602ec8d 100644
--- a/language-web/package.json
+++ b/language-web/package.json
@@ -4,7 +4,7 @@
   "description": "Web frontend for VIATRA-Generator",
   "main": "index.js",
   "scripts": {
-    "assemble:lezer": "lezer-generator src/main/js/editor/problem.grammar -o build/generated/sources/lezer/problem.ts",
+    "assemble:lezer": "lezer-generator src/main/js/language/problem.grammar -o build/generated/sources/lezer/problem.ts",
     "assemble:webpack": "webpack --node-env production",
     "serve": "webpack serve --node-env development --hot",
     "check": "yarn run check:eslint && yarn run check:stylelint",
diff --git a/language-web/src/main/css/xtext/xtext-codemirror.css b/language-web/src/main/css/xtext/xtext-codemirror.css
deleted file mode 100644
index 831b6daf..00000000
--- a/language-web/src/main/css/xtext/xtext-codemirror.css
+++ /dev/null
@@ -1,58 +0,0 @@
-.CodeMirror {
-        height: 100%;
-}
-
-.annotations-gutter {
-        width: 12px;
-        background: #f0f0f0;
-}
-
-.xtext-annotation_error {
-        width: 12px;
-        height: 12px;
-        background-image: url('images/error_an.gif');
-        background-repeat: no-repeat;
-}
-
-.xtext-annotation_warning {
-        width: 12px;
-        height: 12px;
-        background-image: url('images/warning_an.gif');
-        background-repeat: no-repeat;
-}
-
-.xtext-annotation_info {
-        width: 12px;
-        height: 12px;
-        background-image: url('images/info_an.gif');
-        background-repeat: no-repeat;
-}
-
-.xtext-marker_error {
-        z-index: 30;
-        background-image: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAQAAAADCAYAAAC09K7GAAAABmJLR0QA/wD/AP+gvaeTAAAAHElEQVQI12NggIL/DAz/GdA5/xkY/qPKMDAwAADLZwf5rvm+LQAAAABJRU5ErkJggg==");
-        background-repeat: repeat-x;
-        background-position: left bottom;
-}
-
-.xtext-marker_warning {
-        z-index: 20;
-        background-image: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAQAAAADCAYAAAC09K7GAAAABmJLR0QA/wD/AP+gvaeTAAAAMklEQVQI12NkgIIvJ3QXMjAwdDN+OaEbysDA4MPAwNDNwMCwiOHLCd1zX07o6kBVGQEAKBANtobskNMAAAAASUVORK5CYII=");
-        background-repeat: repeat-x;
-        background-position: left bottom;
-}
-
-.xtext-marker_info {
-        z-index: 10;
-        background-image: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAQAAAADCAYAAAC09K7GAAAABmJLR0QA/wD/AP+gvaeTAAAANklEQVQI12NkgIIVRx8tZGBg6GZccfRRKAMDgw8DA0M3AwPDIiYGBoZKBgaG7ghruSsMDAwpABH5CoqwzCoTAAAAAElFTkSuQmCC");
-        background-repeat: repeat-x;
-        background-position: left bottom;
-}
-
-.xtext-marker_read {
-        background-color: #ddd;
-}
-
-.xtext-marker_write {
-        background-color: yellow;
-}
diff --git a/language-web/src/main/images/error_an.gif b/language-web/src/main/images/error_an.gif
deleted file mode 100644
index e014ce90..00000000
--- a/language-web/src/main/images/error_an.gif
+++ /dev/null
diff --git a/language-web/src/main/images/info_an.gif b/language-web/src/main/images/info_an.gif
deleted file mode 100644
index d62ad9dd..00000000
--- a/language-web/src/main/images/info_an.gif
+++ /dev/null
diff --git a/language-web/src/main/images/warning_an.gif b/language-web/src/main/images/warning_an.gif
deleted file mode 100644
index 9ef66dd7..00000000
--- a/language-web/src/main/images/warning_an.gif
+++ /dev/null
diff --git a/language-web/src/main/js/editor/EditorStore.ts b/language-web/src/main/js/editor/EditorStore.ts
index dcc69fd1..be9295bf 100644
--- a/language-web/src/main/js/editor/EditorStore.ts
+++ b/language-web/src/main/js/editor/EditorStore.ts
@@ -42,10 +42,10 @@ import {
   reaction,
 } from 'mobx';
 
+import { problemLanguageSupport } from '../language/problemLanguageSupport';
 import { getLogger } from '../logging';
-import { problemLanguageSupport } from './problemLanguageSupport';
 import type { ThemeStore } from '../theme/ThemeStore';
-import { XtextClient } from './XtextClient';
+import { XtextClient } from '../xtext/XtextClient';
 
 const log = getLogger('EditorStore');
 
diff --git a/language-web/src/main/js/editor/folding.ts b/language-web/src/main/js/language/folding.ts
index 54c7294d..54c7294d 100644
--- a/language-web/src/main/js/editor/folding.ts
+++ b/language-web/src/main/js/language/folding.ts
diff --git a/language-web/src/main/js/editor/indentation.ts b/language-web/src/main/js/language/indentation.ts
index b2f0134b..b2f0134b 100644
--- a/language-web/src/main/js/editor/indentation.ts
+++ b/language-web/src/main/js/language/indentation.ts
diff --git a/language-web/src/main/js/editor/problem.grammar b/language-web/src/main/js/language/problem.grammar
index cf940698..cf940698 100644
--- a/language-web/src/main/js/editor/problem.grammar
+++ b/language-web/src/main/js/language/problem.grammar
diff --git a/language-web/src/main/js/editor/problemLanguageSupport.ts b/language-web/src/main/js/language/problemLanguageSupport.ts
index c9e61b31..c9e61b31 100644
--- a/language-web/src/main/js/editor/problemLanguageSupport.ts
+++ b/language-web/src/main/js/language/problemLanguageSupport.ts
diff --git a/language-web/src/main/js/xtext/CodeMirrorEditorContext.js b/language-web/src/main/js/xtext/CodeMirrorEditorContext.js
deleted file mode 100644
index b829c680..00000000
--- a/language-web/src/main/js/xtext/CodeMirrorEditorContext.js
+++ /dev/null
@@ -1,111 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define([], function() {
-        
-        /**
-         * An editor context mediates between the Xtext services and the CodeMirror editor framework.
-         */
-        function CodeMirrorEditorContext(editor) {
-                this._editor = editor;
-                this._serverState = {};
-                this._serverStateListeners = [];
-                this._dirty = false;
-                this._dirtyStateListeners = [];
-        };
-
-        CodeMirrorEditorContext.prototype = {
-                
-                getServerState: function() {
-                        return this._serverState;
-                },
-                
-                updateServerState: function(currentText, currentStateId) {
-                        this._serverState.text = currentText;
-                        this._serverState.stateId = currentStateId;
-                        return this._serverStateListeners;
-                },
-                
-                addServerStateListener: function(listener) {
-                        this._serverStateListeners.push(listener);
-                },
-                
-                getCaretOffset: function() {
-                        var editor = this._editor;
-                        return editor.indexFromPos(editor.getCursor());
-                },
-                
-                getLineStart: function(lineNumber) {
-                        var editor = this._editor;
-                        return editor.indexFromPos({line: lineNumber, ch: 0});
-                },
-                
-                getSelection: function() {
-                        var editor = this._editor;
-                return {
-                        start: editor.indexFromPos(editor.getCursor('from')),
-                        end: editor.indexFromPos(editor.getCursor('to'))
-                };
-                },
-                
-                getText: function(start, end) {
-                        var editor = this._editor;
-                        if (start && end) {
-                                return editor.getRange(editor.posFromIndex(start), editor.posFromIndex(end));
-                        } else {
-                                return editor.getValue();
-                        }
-                },
-                
-                isDirty: function() {
-                        return !this._clean;
-                },
-                
-                setDirty: function(dirty) {
-                        if (dirty != this._dirty) {
-                                for (var i = 0; i < this._dirtyStateListeners.length; i++) {
-                                        this._dirtyStateListeners[i](dirty);
-                                }
-                        }
-                        this._dirty = dirty;
-                },
-                
-                addDirtyStateListener: function(listener) {
-                        this._dirtyStateListeners.push(listener);
-                },
-                
-                clearUndoStack: function() {
-                        this._editor.clearHistory();
-                },
-                
-                setCaretOffset: function(offset) {
-                        var editor = this._editor;
-                        editor.setCursor(editor.posFromIndex(offset));
-                },
-                
-                setSelection: function(selection) {
-                        var editor = this._editor;
-                        editor.setSelection(editor.posFromIndex(selection.start), editor.posFromIndex(selection.end));
-                },
-                
-                setText: function(text, start, end) {
-                        var editor = this._editor;
-                        if (!start)
-                                start = 0;
-                        if (!end)
-                                end = editor.getValue().length;
-                        var cursor = editor.getCursor();
-                        editor.replaceRange(text, editor.posFromIndex(start), editor.posFromIndex(end));
-                        editor.setCursor(cursor);
-                }
-                
-        };
-        
-        return CodeMirrorEditorContext;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/ContentAssistService.ts b/language-web/src/main/js/xtext/ContentAssistService.ts
new file mode 100644
index 00000000..91789864
--- /dev/null
+++ b/language-web/src/main/js/xtext/ContentAssistService.ts
@@ -0,0 +1,133 @@
+import type {
+  Completion,
+  CompletionContext,
+  CompletionResult,
+} from '@codemirror/autocomplete';
+import type { ChangeSet, Transaction } from '@codemirror/state';
+
+import { getLogger } from '../logging';
+import type { UpdateService } from './UpdateService';
+
+const log = getLogger('xtext.ContentAssistService');
+
+export class ContentAssistService {
+  updateService: UpdateService;
+
+  lastCompletion: CompletionResult | null = null;
+
+  constructor(updateService: UpdateService) {
+    this.updateService = updateService;
+  }
+
+  onTransaction(transaction: Transaction): void {
+    if (this.shouldInvalidateCachedCompletion(transaction.changes)) {
+      this.lastCompletion = null;
+    }
+  }
+
+  async contentAssist(context: CompletionContext): Promise<CompletionResult> {
+    const tokenBefore = context.tokenBefore(['QualifiedName']);
+    let range: { from: number, to: number };
+    let selection: { selectionStart?: number, selectionEnd?: number };
+    if (tokenBefore === null) {
+      if (!context.explicit) {
+        return {
+          from: context.pos,
+          options: [],
+        };
+      }
+      range = {
+        from: context.pos,
+        to: context.pos,
+      };
+      selection = {};
+    } else {
+      range = {
+        from: tokenBefore.from,
+        to: tokenBefore.to,
+      };
+      selection = {
+        selectionStart: tokenBefore.from,
+        selectionEnd: tokenBefore.to,
+      };
+    }
+    if (!context.explicit && this.shouldReturnCachedCompletion(tokenBefore)) {
+      log.trace('Returning cached completion result');
+      // Postcondition of `shouldReturnCachedCompletion`: `lastCompletion !== null`
+      return {
+        ...this.lastCompletion as CompletionResult,
+        ...range,
+      };
+    }
+    this.lastCompletion = null;
+    const entries = await this.updateService.fetchContentAssist({
+      resource: this.updateService.resourceName,
+      serviceType: 'assist',
+      caretOffset: context.pos,
+      ...selection,
+    }, context);
+    if (context.aborted) {
+      return {
+        ...range,
+        options: [],
+      };
+    }
+    const options: Completion[] = [];
+    entries.forEach((entry) => {
+      options.push({
+        label: entry.proposal,
+        detail: entry.description,
+        info: entry.documentation,
+        type: entry.kind?.toLowerCase(),
+        boost: entry.kind === 'KEYWORD' ? -90 : 0,
+      });
+    });
+    log.debug('Fetched', options.length, 'completions from server');
+    this.lastCompletion = {
+      ...range,
+      options,
+      span: /^[a-zA-Z0-9_:]*$/,
+    };
+    return this.lastCompletion;
+  }
+
+  private shouldReturnCachedCompletion(
+    token: { from: number, to: number, text: string } | null,
+  ) {
+    if (token === null || this.lastCompletion === null) {
+      return false;
+    }
+    const { from, to, text } = token;
+    const { from: lastFrom, to: lastTo, span } = this.lastCompletion;
+    if (!lastTo) {
+      return true;
+    }
+    const [transformedFrom, transformedTo] = this.mapRangeInclusive(lastFrom, lastTo);
+    return from >= transformedFrom && to <= transformedTo && span && span.exec(text);
+  }
+
+  private shouldInvalidateCachedCompletion(changes: ChangeSet) {
+    if (changes.empty || this.lastCompletion === null) {
+      return false;
+    }
+    const { from: lastFrom, to: lastTo } = this.lastCompletion;
+    if (!lastTo) {
+      return true;
+    }
+    const [transformedFrom, transformedTo] = this.mapRangeInclusive(lastFrom, lastTo);
+    let invalidate = false;
+    changes.iterChangedRanges((fromA, toA) => {
+      if (fromA < transformedFrom || toA > transformedTo) {
+        invalidate = true;
+      }
+    });
+    return invalidate;
+  }
+
+  private mapRangeInclusive(lastFrom: number, lastTo: number): [number, number] {
+    const changes = this.updateService.computeChangesSinceLastUpdate();
+    const transformedFrom = changes.mapPos(lastFrom);
+    const transformedTo = changes.mapPos(lastTo, 1);
+    return [transformedFrom, transformedTo];
+  }
+}
diff --git a/language-web/src/main/js/xtext/ServiceBuilder.js b/language-web/src/main/js/xtext/ServiceBuilder.js
deleted file mode 100644
index 57fcb310..00000000
--- a/language-web/src/main/js/xtext/ServiceBuilder.js
+++ /dev/null
@@ -1,285 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- ******************************************************************************/
-
-define([
-    'jquery',
-    'xtext/services/XtextService',
-        'xtext/services/LoadResourceService',
-        'xtext/services/SaveResourceService',
-        'xtext/services/HighlightingService',
-        'xtext/services/ValidationService',
-        'xtext/services/UpdateService',
-        'xtext/services/ContentAssistService',
-        'xtext/services/HoverService',
-        'xtext/services/OccurrencesService',
-        'xtext/services/FormattingService',
-  '../logging',
-], function(jQuery, XtextService, LoadResourceService, SaveResourceService, HighlightingService,
-                ValidationService, UpdateService, ContentAssistService, HoverService, OccurrencesService,
-                FormattingService, logging) {
-        
-        /**
-         * Builder class for the Xtext services.
-         */
-        function ServiceBuilder(xtextServices) {
-                this.services = xtextServices;
-        };
-
-        /**
-         * Create all the available Xtext services depending on the configuration.
-         */
-        ServiceBuilder.prototype.createServices = function() {
-                var services = this.services;
-                var options = services.options;
-                var editorContext = services.editorContext;
-                editorContext.xtextServices = services;
-                var self = this;
-                if (!options.serviceUrl) {
-                        if (!options.baseUrl)
-                                options.baseUrl = '/';
-                        else if (options.baseUrl.charAt(0) != '/')
-                                options.baseUrl = '/' + options.baseUrl;
-                        options.serviceUrl = window.location.protocol + '//' + window.location.host + options.baseUrl + 'xtext-service';
-                }
-                if (options.resourceId) {
-                        if (!options.xtextLang)
-                                options.xtextLang = options.resourceId.split(/[?#]/)[0].split('.').pop();
-                        if (options.loadFromServer === undefined)
-                                options.loadFromServer = true;
-                        if (options.loadFromServer && this.setupPersistenceServices) {
-                                services.loadResourceService = new LoadResourceService(options.serviceUrl, options.resourceId, false);
-                                services.loadResource = function(addParams) {
-                                        return services.loadResourceService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                                }
-                                services.saveResourceService = new SaveResourceService(options.serviceUrl, options.resourceId);
-                                services.saveResource = function(addParams) {
-                                        return services.saveResourceService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                                }
-                                services.revertResourceService = new LoadResourceService(options.serviceUrl, options.resourceId, true);
-                                services.revertResource = function(addParams) {
-                                        return services.revertResourceService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                                }
-                                this.setupPersistenceServices();
-                                services.loadResource();
-                        }
-                } else {
-                        if (options.loadFromServer === undefined)
-                                options.loadFromServer = false;
-                        if (options.xtextLang) {
-                                var randomId = Math.floor(Math.random() * 2147483648).toString(16);
-                                options.resourceId = randomId + '.' + options.xtextLang;
-                        }
-                }
-                
-                if (this.setupSyntaxHighlighting) {
-                        this.setupSyntaxHighlighting();
-                }
-                if (options.enableHighlightingService || options.enableHighlightingService === undefined) {
-                        services.highlightingService = new HighlightingService(options.serviceUrl, options.resourceId);
-                        services.computeHighlighting = function(addParams) {
-                                return services.highlightingService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                        }
-                }
-                if (options.enableValidationService || options.enableValidationService === undefined) {
-                        services.validationService = new ValidationService(options.serviceUrl, options.resourceId);
-                        services.validate = function(addParams) {
-                                return services.validationService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                        }
-                }
-                if (this.setupUpdateService) {
-                        function refreshDocument() {
-                                if (services.highlightingService && self.doHighlighting) {
-                                        services.highlightingService.setState(undefined);
-                                        self.doHighlighting();
-                                }
-                                if (services.validationService && self.doValidation) {
-                                        services.validationService.setState(undefined);
-                                        self.doValidation();
-                                }
-                        }
-                        if (!options.sendFullText) {
-                                services.updateService = new UpdateService(options.serviceUrl, options.resourceId);
-                                services.update = function(addParams) {
-                                        return services.updateService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                                }
-                                if (services.saveResourceService)
-                                        services.saveResourceService._updateService = services.updateService;
-                                editorContext.addServerStateListener(refreshDocument);
-                        }
-                        this.setupUpdateService(refreshDocument);
-                }
-                if ((options.enableContentAssistService || options.enableContentAssistService === undefined)
-                                && this.setupContentAssistService) {
-                        services.contentAssistService = new ContentAssistService(options.serviceUrl, options.resourceId, services.updateService);
-                        services.getContentAssist = function(addParams) {
-                                return services.contentAssistService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                        }
-                        this.setupContentAssistService();
-                }
-                if ((options.enableHoverService || options.enableHoverService === undefined)
-                                && this.setupHoverService) {
-                        services.hoverService = new HoverService(options.serviceUrl, options.resourceId, services.updateService);
-                        services.getHoverInfo = function(addParams) {
-                                return services.hoverService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                        }
-                        this.setupHoverService();
-                }
-                if ((options.enableOccurrencesService || options.enableOccurrencesService === undefined)
-                                && this.setupOccurrencesService) {
-                        services.occurrencesService = new OccurrencesService(options.serviceUrl, options.resourceId, services.updateService);
-                        services.getOccurrences = function(addParams) {
-                                return services.occurrencesService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                        }
-                        this.setupOccurrencesService();
-                }
-                if ((options.enableFormattingService || options.enableFormattingService === undefined)
-                                && this.setupFormattingService) {
-                        services.formattingService = new FormattingService(options.serviceUrl, options.resourceId, services.updateService);
-                        services.format = function(addParams) {
-                                return services.formattingService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                        }
-                        this.setupFormattingService();
-                }
-                if (options.enableGeneratorService || options.enableGeneratorService === undefined) {
-                        services.generatorService = new XtextService();
-                        services.generatorService.initialize(services, 'generate');
-                        services.generatorService._initServerData = function(serverData, editorContext, params) {
-                                if (params.allArtifacts)
-                                        serverData.allArtifacts = params.allArtifacts;
-                                else if (params.artifactId)
-                                        serverData.artifact = params.artifactId;
-                                if (params.includeContent !== undefined)
-                                        serverData.includeContent = params.includeContent;
-                        }
-                        services.generate = function(addParams) {
-                                return services.generatorService.invoke(editorContext, ServiceBuilder.mergeOptions(addParams, options));
-                        }
-                }
-                
-                if (options.dirtyElement) {
-                        var doc = options.document || document;
-                        var dirtyElement;
-                        if (typeof(options.dirtyElement) === 'string')
-                                dirtyElement = jQuery('#' + options.dirtyElement, doc);
-                        else
-                                dirtyElement = jQuery(options.dirtyElement);
-                        var dirtyStatusClass = options.dirtyStatusClass;
-                        if (!dirtyStatusClass)
-                                dirtyStatusClass = 'dirty';
-                        editorContext.addDirtyStateListener(function(dirty) {
-                                if (dirty)
-                                        dirtyElement.addClass(dirtyStatusClass);
-                                else
-                                        dirtyElement.removeClass(dirtyStatusClass);
-                        });
-                }
-                
-    const log = logging.getLoggerFromRoot('xtext.XtextService');
-                services.successListeners = [function(serviceType, result) {
-      if (log.getLevel() <= log.levels.TRACE) {
-        log.trace('service', serviceType, 'request success', JSON.parse(JSON.stringify(result)));
-      }
-    }];
-                services.errorListeners = [function(serviceType, severity, message, requestData) {
-      const messageParts = ['service', serviceType, 'failed:', message || '(no message)'];
-      if (requestData) {
-        messageParts.push(JSON.parse(JSON.stringify(requestData)));
-      }
-      if (severity === 'warning') {
-                                log.warn(...messageParts);
-      } else {
-        log.error(...messageParts);
-      }
-                }];
-        }
-        
-        /**
-         * Change the resource associated with this service builder.
-         */
-        ServiceBuilder.prototype.changeResource = function(resourceId) {
-                var services = this.services;
-                var options = services.options;
-                options.resourceId = resourceId;
-                for (var p in services) {
-                        if (services.hasOwnProperty(p)) {
-                                var service = services[p];
-                                if (service._serviceType && jQuery.isFunction(service.initialize))
-                                        services[p].initialize(options.serviceUrl, service._serviceType, resourceId, services.updateService);
-                        }
-                }
-                var knownServerState = services.editorContext.getServerState();
-                delete knownServerState.stateId;
-                delete knownServerState.text;
-                if (options.loadFromServer && jQuery.isFunction(services.loadResource)) {
-                        services.loadResource();
-                }
-        }
-        
-        /**
-         * Create a copy of the given object.
-         */
-        ServiceBuilder.copy = function(obj) {
-                var copy = {};
-                for (var p in obj) {
-                        if (obj.hasOwnProperty(p))
-                                copy[p] = obj[p];
-                }
-                return copy;
-        }
-        
-        /**
-         * Translate an HTML attribute name to a JS option name.
-         */
-        ServiceBuilder.optionName = function(name) {
-                var prefix = 'data-editor-';
-                if (name.substring(0, prefix.length) === prefix) {
-                        var key = name.substring(prefix.length);
-                        key = key.replace(/-([a-z])/ig, function(all, character) {
-                                return character.toUpperCase();
-                        });
-                        return key;
-                }
-                return undefined;
-        }
-        
-        /**
-         * Copy all default options into the given set of additional options.
-         */
-        ServiceBuilder.mergeOptions = function(options, defaultOptions) {
-                if (options) {
-                        for (var p in defaultOptions) {
-                                if (defaultOptions.hasOwnProperty(p))
-                                        options[p] = defaultOptions[p];
-                        }
-                        return options;
-                } else {
-                        return ServiceBuilder.copy(defaultOptions);
-                }
-        }
-        
-        /**
-         * Merge all properties of the given parent element with the given default options.
-         */
-        ServiceBuilder.mergeParentOptions = function(parent, defaultOptions) {
-                var options = ServiceBuilder.copy(defaultOptions);
-                for (var attr, j = 0, attrs = parent.attributes, l = attrs.length; j < l; j++) {
-                        attr = attrs.item(j);
-                        var key = ServiceBuilder.optionName(attr.nodeName);
-                        if (key) {
-                                var value = attr.nodeValue;
-                                if (value === 'true' || value === 'false')
-                                        value = value === 'true';
-                                options[key] = value;
-                        }
-                }
-                return options;
-        }
-        
-        return ServiceBuilder;
-});
diff --git a/language-web/src/main/js/editor/XtextClient.ts b/language-web/src/main/js/xtext/UpdateService.ts
index 6f789fb7..f8ab7438 100644
--- a/language-web/src/main/js/editor/XtextClient.ts
+++ b/language-web/src/main/js/xtext/UpdateService.ts
@@ -1,132 +1,71 @@
 import {
-  Completion,
-  CompletionContext,
-  CompletionResult,
-} from '@codemirror/autocomplete';
-import type { Diagnostic } from '@codemirror/lint';
-import {
   ChangeDesc,
   ChangeSet,
   Transaction,
 } from '@codemirror/state';
 import { nanoid } from 'nanoid';
 
-import type { EditorStore } from './EditorStore';
+import type { EditorStore } from '../editor/EditorStore';
 import { getLogger } from '../logging';
+import type { XtextWebSocketClient } from './XtextWebSocketClient';
+import { PendingTask } from '../utils/PendingTask';
 import { Timer } from '../utils/Timer';
 import {
   IContentAssistEntry,
   isContentAssistResult,
   isDocumentStateResult,
   isInvalidStateIdConflictResult,
-  isValidationResult,
 } from './xtextServiceResults';
-import { XtextWebSocketClient } from './XtextWebSocketClient';
-import { PendingTask } from '../utils/PendingTask';
 
 const UPDATE_TIMEOUT_MS = 500;
 
 const WAIT_FOR_UPDATE_TIMEOUT_MS = 1000;
 
-const log = getLogger('XtextClient');
+const log = getLogger('xtext.UpdateService');
 
-export class XtextClient {
-  resourceName: string;
+export interface IAbortSignal {
+  aborted: boolean;
+}
 
-  webSocketClient: XtextWebSocketClient;
+export class UpdateService {
+  resourceName: string;
 
   xtextStateId: string | null = null;
 
-  pendingUpdate: ChangeDesc | null;
+  private store: EditorStore;
 
-  dirtyChanges: ChangeDesc;
+  private pendingUpdate: ChangeDesc | null = null;
 
-  lastCompletion: CompletionResult | null = null;
+  private dirtyChanges: ChangeDesc;
 
-  updateListeners: PendingTask<void>[] = [];
+  private webSocketClient: XtextWebSocketClient;
 
-  updateTimer = new Timer(() => {
-    this.handleUpdate();
-  }, UPDATE_TIMEOUT_MS);
+  private updateListeners: PendingTask<void>[] = [];
 
-  store: EditorStore;
+  private idleUpdateTimer = new Timer(() => {
+    this.handleIdleUpdate();
+  }, UPDATE_TIMEOUT_MS);
 
-  constructor(store: EditorStore) {
+  constructor(store: EditorStore, webSocketClient: XtextWebSocketClient) {
     this.resourceName = `${nanoid(7)}.problem`;
-    this.pendingUpdate = null;
     this.store = store;
     this.dirtyChanges = this.newEmptyChangeDesc();
-    this.webSocketClient = new XtextWebSocketClient(
-      async () => {
-        this.xtextStateId = null;
-        await this.updateFullText();
-      },
-      async (resource, stateId, service, push) => {
-        await this.onPush(resource, stateId, service, push);
-      },
-    );
+    this.webSocketClient = webSocketClient;
   }
 
   onTransaction(transaction: Transaction): void {
     const { changes } = transaction;
     if (!changes.empty) {
-      if (this.shouldInvalidateCachedCompletion(transaction)) {
-        log.trace('Invalidating cached completions');
-        this.lastCompletion = null;
-      }
       this.dirtyChanges = this.dirtyChanges.composeDesc(changes.desc);
-      this.updateTimer.reschedule();
-    }
-  }
-
-  private async onPush(resource: string, stateId: string, service: string, push: unknown) {
-    if (resource !== this.resourceName) {
-      log.error('Unknown resource name: expected:', this.resourceName, 'got:', resource);
-      return;
+      this.idleUpdateTimer.reschedule();
     }
-    if (stateId !== this.xtextStateId) {
-      log.error('Unexpected xtext state id: expected:', this.xtextStateId, 'got:', resource);
-      await this.updateFullText();
-    }
-    switch (service) {
-      case 'validate':
-        this.onValidate(push);
-        return;
-      case 'highlight':
-        // TODO
-        return;
-      default:
-        log.error('Unknown push service:', service);
-        break;
-    }
-  }
-
-  private onValidate(push: unknown) {
-    if (!isValidationResult(push)) {
-      log.error('Invalid validation result', push);
-      return;
-    }
-    const allChanges = this.computeChangesSinceLastUpdate();
-    const diagnostics: Diagnostic[] = [];
-    push.issues.forEach((issue) => {
-      if (issue.severity === 'ignore') {
-        return;
-      }
-      diagnostics.push({
-        from: allChanges.mapPos(issue.offset),
-        to: allChanges.mapPos(issue.offset + issue.length),
-        severity: issue.severity,
-        message: issue.description,
-      });
-    });
-    this.store.updateDiagnostics(diagnostics);
   }
 
-  private computeChangesSinceLastUpdate() {
+  computeChangesSinceLastUpdate(): ChangeDesc {
     return this.pendingUpdate?.composeDesc(this.dirtyChanges) || this.dirtyChanges;
   }
 
-  private handleUpdate() {
+  private handleIdleUpdate() {
     if (!this.webSocketClient.isOpen || this.dirtyChanges.empty) {
       return;
     }
@@ -135,7 +74,7 @@ export class XtextClient {
         log.error('Unexpected error during scheduled update', error);
       });
     }
-    this.updateTimer.reschedule();
+    this.idleUpdateTimer.reschedule();
   }
 
   private newEmptyChangeDesc() {
@@ -143,7 +82,7 @@ export class XtextClient {
     return changeSet.desc;
   }
 
-  private async updateFullText() {
+  async updateFullText(): Promise<void> {
     await this.withUpdate(() => this.doUpdateFullText());
   }
 
@@ -196,99 +135,24 @@ export class XtextClient {
     return this.doUpdateFullText();
   }
 
-  async contentAssist(context: CompletionContext): Promise<CompletionResult> {
-    const tokenBefore = context.tokenBefore(['QualifiedName']);
-    if (tokenBefore === null && !context.explicit) {
-      return {
-        from: context.pos,
-        options: [],
-      };
-    }
-    const range = {
-      from: tokenBefore?.from || context.pos,
-      to: tokenBefore?.to || context.pos,
-    };
-    if (this.shouldReturnCachedCompletion(tokenBefore)) {
-      log.trace('Returning cached completion result');
-      // Postcondition of `shouldReturnCachedCompletion`: `lastCompletion !== null`
-      return {
-        ...this.lastCompletion as CompletionResult,
-        ...range,
-      };
-    }
-    const entries = await this.fetchContentAssist(context);
-    if (context.aborted) {
-      return {
-        ...range,
-        options: [],
-      };
-    }
-    const options: Completion[] = [];
-    entries.forEach((entry) => {
-      options.push({
-        label: entry.proposal,
-        detail: entry.description,
-        info: entry.documentation,
-        type: entry.kind?.toLowerCase(),
-        boost: entry.kind === 'KEYWORD' ? -90 : 0,
-      });
-    });
-    log.debug('Fetched', options.length, 'completions from server');
-    this.lastCompletion = {
-      ...range,
-      options,
-      span: /[a-zA-Z0-9_:]/,
-    };
-    return this.lastCompletion;
-  }
-
-  private shouldReturnCachedCompletion(
-    token: { from: number, to: number, text: string } | null,
-  ) {
-    if (token === null || this.lastCompletion === null) {
-      return false;
-    }
-    const { from, to, text } = token;
-    const { from: lastFrom, to: lastTo, span } = this.lastCompletion;
-    if (!lastTo) {
-      return true;
-    }
-    const transformedFrom = this.dirtyChanges.mapPos(lastFrom);
-    const transformedTo = this.dirtyChanges.mapPos(lastTo, 1);
-    return from >= transformedFrom && to <= transformedTo && span && span.exec(text);
-  }
-
-  private shouldInvalidateCachedCompletion(transaction: Transaction) {
-    if (this.lastCompletion === null) {
-      return false;
-    }
-    const { from: lastFrom, to: lastTo } = this.lastCompletion;
-    if (!lastTo) {
-      return true;
-    }
-    const transformedFrom = this.dirtyChanges.mapPos(lastFrom);
-    const transformedTo = this.dirtyChanges.mapPos(lastTo, 1);
-    let invalidate = false;
-    transaction.changes.iterChangedRanges((fromA, toA) => {
-      if (fromA < transformedFrom || toA > transformedTo) {
-        invalidate = true;
-      }
-    });
-    return invalidate;
-  }
-
-  private async fetchContentAssist(context: CompletionContext) {
+  async fetchContentAssist(
+    params: Record<string, unknown>,
+    signal: IAbortSignal,
+  ): Promise<IContentAssistEntry[]> {
     await this.prepareForDeltaUpdate();
+    if (signal.aborted) {
+      return [];
+    }
     const delta = this.computeDelta();
     if (delta === null) {
       // Poscondition of `prepareForDeltaUpdate`: `xtextStateId !== null`
-      return this.doFetchContentAssist(context, this.xtextStateId as string);
+      return this.doFetchContentAssist(params, this.xtextStateId as string);
     }
     log.trace('Editor delta', delta);
-    return await this.withUpdate(async () => {
+    return this.withUpdate(async () => {
       const result = await this.webSocketClient.send({
+        ...params,
         requiredStateId: this.xtextStateId,
-        ...this.computeContentAssistParams(context),
         ...delta,
       });
       if (isContentAssistResult(result)) {
@@ -296,10 +160,10 @@ export class XtextClient {
       }
       if (isInvalidStateIdConflictResult(result)) {
         const [newStateId] = await this.doFallbackToUpdateFullText();
-        if (context.aborted) {
-          return [newStateId, [] as IContentAssistEntry[]];
+        if (signal.aborted) {
+          return [newStateId, []];
         }
-        const entries = await this.doFetchContentAssist(context, newStateId);
+        const entries = await this.doFetchContentAssist(params, newStateId);
         return [newStateId, entries];
       }
       log.error('Unextpected content assist result with delta update', result);
@@ -307,10 +171,10 @@ export class XtextClient {
     });
   }
 
-  private async doFetchContentAssist(context: CompletionContext, expectedStateId: string) {
+  private async doFetchContentAssist(params: Record<string, unknown>, expectedStateId: string) {
     const result = await this.webSocketClient.send({
+      ...params,
       requiredStateId: expectedStateId,
-      ...this.computeContentAssistParams(context),
     });
     if (isContentAssistResult(result) && result.stateId === expectedStateId) {
       return result.entries;
@@ -319,23 +183,6 @@ export class XtextClient {
     throw new Error('Unexpected content assist result');
   }
 
-  private computeContentAssistParams(context: CompletionContext) {
-    const tokenBefore = context.tokenBefore(['QualifiedName']);
-    let selection = {};
-    if (tokenBefore !== null) {
-      selection = {
-        selectionStart: tokenBefore.from,
-        selectionEnd: tokenBefore.to,
-      };
-    }
-    return {
-      resource: this.resourceName,
-      serviceType: 'assist',
-      caretOffset: tokenBefore?.from || context.pos,
-      ...selection,
-    };
-  }
-
   private computeDelta() {
     if (this.dirtyChanges.empty) {
       return null;
diff --git a/language-web/src/main/js/xtext/ValidationService.ts b/language-web/src/main/js/xtext/ValidationService.ts
new file mode 100644
index 00000000..838aa31e
--- /dev/null
+++ b/language-web/src/main/js/xtext/ValidationService.ts
@@ -0,0 +1,40 @@
+import type { Diagnostic } from '@codemirror/lint';
+
+import type { EditorStore } from '../editor/EditorStore';
+import { getLogger } from '../logging';
+import type { UpdateService } from './UpdateService';
+import { isValidationResult } from './xtextServiceResults';
+
+const log = getLogger('xtext.ValidationService');
+
+export class ValidationService {
+  private store: EditorStore;
+
+  private updateService: UpdateService;
+
+  constructor(store: EditorStore, updateService: UpdateService) {
+    this.store = store;
+    this.updateService = updateService;
+  }
+
+  onPush(push: unknown): void {
+    if (!isValidationResult(push)) {
+      log.error('Invalid validation result', push);
+      return;
+    }
+    const allChanges = this.updateService.computeChangesSinceLastUpdate();
+    const diagnostics: Diagnostic[] = [];
+    push.issues.forEach((issue) => {
+      if (issue.severity === 'ignore') {
+        return;
+      }
+      diagnostics.push({
+        from: allChanges.mapPos(issue.offset),
+        to: allChanges.mapPos(issue.offset + issue.length),
+        severity: issue.severity,
+        message: issue.description,
+      });
+    });
+    this.store.updateDiagnostics(diagnostics);
+  }
+}
diff --git a/language-web/src/main/js/xtext/XtextClient.ts b/language-web/src/main/js/xtext/XtextClient.ts
new file mode 100644
index 00000000..f8b06258
--- /dev/null
+++ b/language-web/src/main/js/xtext/XtextClient.ts
@@ -0,0 +1,73 @@
+import type {
+  CompletionContext,
+  CompletionResult,
+} from '@codemirror/autocomplete';
+import type { Transaction } from '@codemirror/state';
+
+import type { EditorStore } from '../editor/EditorStore';
+import { ContentAssistService } from './ContentAssistService';
+import { getLogger } from '../logging';
+import { UpdateService } from './UpdateService';
+import { ValidationService } from './ValidationService';
+import { XtextWebSocketClient } from './XtextWebSocketClient';
+
+const log = getLogger('xtext.XtextClient');
+
+export class XtextClient {
+  webSocketClient: XtextWebSocketClient;
+
+  updateService: UpdateService;
+
+  contentAssistService: ContentAssistService;
+
+  validationService: ValidationService;
+
+  constructor(store: EditorStore) {
+    this.webSocketClient = new XtextWebSocketClient(
+      async () => {
+        this.updateService.xtextStateId = null;
+        await this.updateService.updateFullText();
+      },
+      async (resource, stateId, service, push) => {
+        await this.onPush(resource, stateId, service, push);
+      },
+    );
+    this.updateService = new UpdateService(store, this.webSocketClient);
+    this.contentAssistService = new ContentAssistService(this.updateService);
+    this.validationService = new ValidationService(store, this.updateService);
+  }
+
+  onTransaction(transaction: Transaction): void {
+    // `ContentAssistService.prototype.onTransaction` needs the dirty change desc
+    // _before_ the current edit, so we call it before `updateService`.
+    this.contentAssistService.onTransaction(transaction);
+    this.updateService.onTransaction(transaction);
+  }
+
+  private async onPush(resource: string, stateId: string, service: string, push: unknown) {
+    const { resourceName, xtextStateId } = this.updateService;
+    if (resource !== resourceName) {
+      log.error('Unknown resource name: expected:', resourceName, 'got:', resource);
+      return;
+    }
+    if (stateId !== xtextStateId) {
+      log.error('Unexpected xtext state id: expected:', xtextStateId, 'got:', resource);
+      await this.updateService.updateFullText();
+    }
+    switch (service) {
+      case 'validate':
+        this.validationService.onPush(push);
+        return;
+      case 'highlight':
+        // TODO
+        return;
+      default:
+        log.error('Unknown push service:', service);
+        break;
+    }
+  }
+
+  contentAssist(context: CompletionContext): Promise<CompletionResult> {
+    return this.contentAssistService.contentAssist(context);
+  }
+}
diff --git a/language-web/src/main/js/editor/XtextWebSocketClient.ts b/language-web/src/main/js/xtext/XtextWebSocketClient.ts
index 5b775500..5b775500 100644
--- a/language-web/src/main/js/editor/XtextWebSocketClient.ts
+++ b/language-web/src/main/js/xtext/XtextWebSocketClient.ts
diff --git a/language-web/src/main/js/xtext/compatibility.js b/language-web/src/main/js/xtext/compatibility.js
deleted file mode 100644
index c877fc56..00000000
--- a/language-web/src/main/js/xtext/compatibility.js
+++ /dev/null
@@ -1,63 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define([], function() {
-        
-        if (!Function.prototype.bind) {
-                Function.prototype.bind = function(target) {
-                        if (typeof this !== 'function')
-                                throw new TypeError('bind target is not callable');
-                        var args = Array.prototype.slice.call(arguments, 1);
-                        var unboundFunc = this;
-                        var nopFunc = function() {};
-                        boundFunc = function() {
-                                var localArgs = Array.prototype.slice.call(arguments);
-                                return unboundFunc.apply(this instanceof nopFunc ? this : target,
-                                                args.concat(localArgs));
-                        };
-                        nopFunc.prototype = this.prototype;
-                        boundFunc.prototype = new nopFunc();
-                        return boundFunc;
-                }
-        }
-        
-        if (!Array.prototype.map) {
-                Array.prototype.map = function(callback, thisArg) {
-                        if (this == null)
-                                throw new TypeError('this is null');
-                        if (typeof callback !== 'function')
-                                throw new TypeError('callback is not callable');
-                        var srcArray = Object(this);
-                        var len = srcArray.length >>> 0;
-                        var tgtArray = new Array(len);
-                        for (var i = 0; i < len; i++) {
-                                if (i in srcArray)
-                                        tgtArray[i] = callback.call(thisArg, srcArray[i], i, srcArray);
-                        }
-                        return tgtArray;
-                }
-        }
-        
-        if (!Array.prototype.forEach) {
-                Array.prototype.forEach = function(callback, thisArg) {
-                        if (this == null)
-                                throw new TypeError('this is null');
-                        if (typeof callback !== 'function')
-                                throw new TypeError('callback is not callable');
-                        var srcArray = Object(this);
-                        var len = srcArray.length >>> 0;
-                        for (var i = 0; i < len; i++) {
-                                if (i in srcArray)
-                                        callback.call(thisArg, srcArray[i], i, srcArray);
-                        }
-                }
-        }
-        
-        return {};
-});
diff --git a/language-web/src/main/js/xtext/services/ContentAssistService.js b/language-web/src/main/js/xtext/services/ContentAssistService.js
deleted file mode 100644
index 1686570d..00000000
--- a/language-web/src/main/js/xtext/services/ContentAssistService.js
+++ /dev/null
@@ -1,132 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-
-        /**
-         * Service class for content assist proposals. The proposals are returned as promise of
-         * a Deferred object.
-         */
-        function ContentAssistService(serviceUrl, resourceId, updateService) {
-                this.initialize(serviceUrl, 'assist', resourceId, updateService);
-        }
-
-        ContentAssistService.prototype = new XtextService();
-        
-        ContentAssistService.prototype.invoke = function(editorContext, params, deferred) {
-                if (deferred === undefined) {
-                        deferred = jQuery.Deferred();
-                }
-                var serverData = {
-                        contentType: params.contentType
-                };
-                if (params.offset)
-                        serverData.caretOffset = params.offset;
-                else
-                        serverData.caretOffset = editorContext.getCaretOffset();
-                var selection = params.selection ? params.selection : editorContext.getSelection();
-                if (selection.start != serverData.caretOffset || selection.end != serverData.caretOffset) {
-                        serverData.selectionStart = selection.start;
-                        serverData.selectionEnd = selection.end;
-                }
-                var currentText;
-                var httpMethod = 'GET';
-                var onComplete = undefined;
-                var knownServerState = editorContext.getServerState();
-                if (params.sendFullText) {
-                        serverData.fullText = editorContext.getText();
-                        httpMethod = 'POST';
-                } else {
-                        serverData.requiredStateId = knownServerState.stateId;
-                        if (this._updateService) {
-                                if (knownServerState.text === undefined || knownServerState.updateInProgress) {
-                                        var self = this;
-                                        this._updateService.addCompletionCallback(function() {
-                                                self.invoke(editorContext, params, deferred);
-                                        });
-                                        return deferred.promise();
-                                }
-                                knownServerState.updateInProgress = true;
-                                onComplete = this._updateService.onComplete.bind(this._updateService);
-                                currentText = editorContext.getText();
-                                this._updateService.computeDelta(knownServerState.text, currentText, serverData);
-                                if (serverData.deltaText !== undefined) {
-                                        httpMethod = 'POST';
-                                }
-                        }
-                }
-                
-                var self = this;
-                self.sendRequest(editorContext, {
-                        type: httpMethod,
-                        data: serverData,
-                        
-                        success: function(result) {
-                                if (result.conflict) {
-                                        // The server has lost its session state and the resource is loaded from the server
-                                        if (self._increaseRecursionCount(editorContext)) {
-                                                if (onComplete) {
-                                                        delete knownServerState.updateInProgress;
-                                                        delete knownServerState.text;
-                                                        delete knownServerState.stateId;
-                                                        self._updateService.addCompletionCallback(function() {
-                                                                self.invoke(editorContext, params, deferred);
-                                                        });
-                                                        self._updateService.invoke(editorContext, params);
-                                                } else {
-                                                        var paramsCopy = {};
-                                                        for (var p in params) {
-                                                                if (params.hasOwnProperty(p))
-                                                                        paramsCopy[p] = params[p];
-                                                        }
-                                                        paramsCopy.sendFullText = true;
-                                                        self.invoke(editorContext, paramsCopy, deferred);
-                                                }
-                                        } else {
-                                                deferred.reject(result.conflict);
-                                        }
-                                        return false;
-                                }
-                                if (onComplete && result.stateId !== undefined && result.stateId != editorContext.getServerState().stateId) {
-                                        var listeners = editorContext.updateServerState(currentText, result.stateId);
-                                        for (var i = 0; i < listeners.length; i++) {
-                                                self._updateService.addCompletionCallback(listeners[i], params);
-                                        }
-                                }
-                                deferred.resolve(result.entries);
-                        },
-                        
-                        error: function(xhr, textStatus, errorThrown) {
-                                if (onComplete && xhr.status == 404 && !params.loadFromServer && knownServerState.text !== undefined) {
-                                        // The server has lost its session state and the resource is not loaded from the server
-                                        delete knownServerState.updateInProgress;
-                                        delete knownServerState.text;
-                                        delete knownServerState.stateId;
-                                        self._updateService.addCompletionCallback(function() {
-                                                self.invoke(editorContext, params, deferred);
-                                        });
-                                        self._updateService.invoke(editorContext, params);
-                                        return true;
-                                }
-                                deferred.reject(errorThrown);
-                        },
-                        
-                        complete: onComplete
-                }, !params.sendFullText);
-                var result = deferred.promise();
-                if (onComplete) {
-                        result.always(function() {
-                                knownServerState.updateInProgress = false;
-                        });
-                }
-                return result;
-        };
-
-        return ContentAssistService;
-});
diff --git a/language-web/src/main/js/xtext/services/FormattingService.js b/language-web/src/main/js/xtext/services/FormattingService.js
deleted file mode 100644
index f59099ee..00000000
--- a/language-web/src/main/js/xtext/services/FormattingService.js
+++ /dev/null
@@ -1,52 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-        
-        /**
-         * Service class for formatting text.
-         */
-        function FormattingService(serviceUrl, resourceId, updateService) {
-                this.initialize(serviceUrl, 'format', resourceId, updateService);
-        };
-
-        FormattingService.prototype = new XtextService();
-
-        FormattingService.prototype._initServerData = function(serverData, editorContext, params) {
-                var selection = params.selection ? params.selection : editorContext.getSelection();
-                if (selection.end > selection.start) {
-                        serverData.selectionStart = selection.start;
-                        serverData.selectionEnd = selection.end;
-                }
-                return {
-                        httpMethod: 'POST'
-                };
-        };
-        
-        FormattingService.prototype._processResult = function(result, editorContext) {
-                // The text update may be asynchronous, so we have to compute the new text ourselves
-                var newText;
-                if (result.replaceRegion) {
-                        var fullText = editorContext.getText();
-                        var start = result.replaceRegion.offset;
-                        var end = result.replaceRegion.offset + result.replaceRegion.length;
-                        editorContext.setText(result.formattedText, start, end);
-                        newText = fullText.substring(0, start) + result.formattedText + fullText.substring(end);
-                } else {
-                        editorContext.setText(result.formattedText);
-                        newText = result.formattedText;
-                }
-                var listeners = editorContext.updateServerState(newText, result.stateId);
-                for (var i = 0; i < listeners.length; i++) {
-                        listeners[i]({});
-                }
-        };
-        
-        return FormattingService;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/services/HighlightingService.js b/language-web/src/main/js/xtext/services/HighlightingService.js
deleted file mode 100644
index 5a5ac8ba..00000000
--- a/language-web/src/main/js/xtext/services/HighlightingService.js
+++ /dev/null
@@ -1,33 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-        
-        /**
-         * Service class for semantic highlighting.
-         */
-        function HighlightingService(serviceUrl, resourceId) {
-                this.initialize(serviceUrl, 'highlight', resourceId);
-        };
-
-        HighlightingService.prototype = new XtextService();
-        
-        HighlightingService.prototype._checkPreconditions = function(editorContext, params) {
-                return this._state === undefined;
-        }
-
-        HighlightingService.prototype._onConflict = function(editorContext, cause) {
-                this.setState(undefined);
-                return {
-                        suppressForcedUpdate: true
-                };
-        };
-        
-        return HighlightingService;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/services/HoverService.js b/language-web/src/main/js/xtext/services/HoverService.js
deleted file mode 100644
index 03c5a52b..00000000
--- a/language-web/src/main/js/xtext/services/HoverService.js
+++ /dev/null
@@ -1,59 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-        
-        /**
-         * Service class for hover information.
-         */
-        function HoverService(serviceUrl, resourceId, updateService) {
-                this.initialize(serviceUrl, 'hover', resourceId, updateService);
-        };
-
-        HoverService.prototype = new XtextService();
-
-        HoverService.prototype._initServerData = function(serverData, editorContext, params) {
-                // In order to display hover info for a selected completion proposal while the content
-                // assist popup is shown, the selected proposal is passed as parameter
-                if (params.proposal && params.proposal.proposal)
-                        serverData.proposal = params.proposal.proposal;
-                if (params.offset)
-                        serverData.caretOffset = params.offset;
-                else
-                        serverData.caretOffset = editorContext.getCaretOffset();
-                var selection = params.selection ? params.selection : editorContext.getSelection();
-                if (selection.start != serverData.caretOffset || selection.end != serverData.caretOffset) {
-                        serverData.selectionStart = selection.start;
-                        serverData.selectionEnd = selection.end;
-                }
-        };
-        
-        HoverService.prototype._getSuccessCallback = function(editorContext, params, deferred) {
-                var delay = params.mouseHoverDelay;
-                if (!delay)
-                        delay = 500;
-                var showTime = new Date().getTime() + delay;
-                return function(result) {
-                        if (result.conflict || !result.title && !result.content) {
-                                deferred.reject();
-                        } else {
-                                var remainingTimeout = Math.max(0, showTime - new Date().getTime());
-                                setTimeout(function() {
-                                        if (!params.sendFullText && result.stateId !== undefined
-                                                        && result.stateId != editorContext.getServerState().stateId) 
-                                                deferred.reject();
-                                        else
-                                                deferred.resolve(result);
-                                }, remainingTimeout);
-                        }
-                };
-        };
-        
-        return HoverService;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/services/LoadResourceService.js b/language-web/src/main/js/xtext/services/LoadResourceService.js
deleted file mode 100644
index b5a315c3..00000000
--- a/language-web/src/main/js/xtext/services/LoadResourceService.js
+++ /dev/null
@@ -1,42 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-        
-        /**
-         * Service class for loading resources. The resulting text is passed to the editor context.
-         */
-        function LoadResourceService(serviceUrl, resourceId, revert) {
-                this.initialize(serviceUrl, revert ? 'revert' : 'load', resourceId);
-        };
-
-        LoadResourceService.prototype = new XtextService();
-        
-        LoadResourceService.prototype._initServerData = function(serverData, editorContext, params) {
-                return {
-                        suppressContent: true,
-                        httpMethod: this._serviceType == 'revert' ? 'POST' : 'GET'
-                };
-        };
-        
-        LoadResourceService.prototype._getSuccessCallback = function(editorContext, params, deferred) {
-                return function(result) {
-                        editorContext.setText(result.fullText);
-                        editorContext.clearUndoStack();
-                        editorContext.setDirty(result.dirty);
-                        var listeners = editorContext.updateServerState(result.fullText, result.stateId);
-                        for (var i = 0; i < listeners.length; i++) {
-                                listeners[i](params);
-                        }
-                        deferred.resolve(result);
-                }
-        }
-
-        return LoadResourceService;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/services/OccurrencesService.js b/language-web/src/main/js/xtext/services/OccurrencesService.js
deleted file mode 100644
index 2e2d0b1a..00000000
--- a/language-web/src/main/js/xtext/services/OccurrencesService.js
+++ /dev/null
@@ -1,39 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-        
-        /**
-         * Service class for marking occurrences.
-         */
-        function OccurrencesService(serviceUrl, resourceId, updateService) {
-                this.initialize(serviceUrl, 'occurrences', resourceId, updateService);
-        };
-
-        OccurrencesService.prototype = new XtextService();
-
-        OccurrencesService.prototype._initServerData = function(serverData, editorContext, params) {
-                if (params.offset)
-                        serverData.caretOffset = params.offset;
-                else
-                        serverData.caretOffset = editorContext.getCaretOffset();
-        };
-        
-        OccurrencesService.prototype._getSuccessCallback = function(editorContext, params, deferred) {
-                return function(result) {
-                        if (result.conflict || !params.sendFullText && result.stateId !== undefined
-                                        && result.stateId != editorContext.getServerState().stateId) 
-                                deferred.reject();
-                        else 
-                                deferred.resolve(result);
-                }
-        }
-
-        return OccurrencesService;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/services/SaveResourceService.js b/language-web/src/main/js/xtext/services/SaveResourceService.js
deleted file mode 100644
index 66cdaff5..00000000
--- a/language-web/src/main/js/xtext/services/SaveResourceService.js
+++ /dev/null
@@ -1,32 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-        
-        /**
-         * Service class for saving resources.
-         */
-        function SaveResourceService(serviceUrl, resourceId) {
-                this.initialize(serviceUrl, 'save', resourceId);
-        };
-
-        SaveResourceService.prototype = new XtextService();
-
-        SaveResourceService.prototype._initServerData = function(serverData, editorContext, params) {
-                return {
-                        httpMethod: 'POST'
-                };
-        };
-        
-        SaveResourceService.prototype._processResult = function(result, editorContext) {
-                editorContext.setDirty(false);
-        };
-        
-        return SaveResourceService;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/services/UpdateService.js b/language-web/src/main/js/xtext/services/UpdateService.js
deleted file mode 100644
index b78d846d..00000000
--- a/language-web/src/main/js/xtext/services/UpdateService.js
+++ /dev/null
@@ -1,159 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-        
-        /**
-         * Service class for updating the server-side representation of a resource.
-         * This service only makes sense with a stateful server, where an update request is sent
-         * after each modification. This can greatly improve response times compared to the
-         * stateless alternative, where the full text content is sent with each service request.
-         */
-        function UpdateService(serviceUrl, resourceId) {
-                this.initialize(serviceUrl, 'update', resourceId, this);
-                this._completionCallbacks = [];
-        };
-        
-        UpdateService.prototype = new XtextService();
-
-        /**
-         * Compute a delta between two versions of a text. If a difference is found, the result
-         * contains three properties:
-         *   deltaText - the text to insert into s1
-         *   deltaOffset - the text insertion offset
-         *   deltaReplaceLength - the number of characters that shall be replaced by the inserted text
-         */
-        UpdateService.prototype.computeDelta = function(s1, s2, result) {
-                var start = 0, s1length = s1.length, s2length = s2.length;
-                while (start < s1length && start < s2length && s1.charCodeAt(start) === s2.charCodeAt(start)) {
-                        start++;
-                }
-                if (start === s1length && start === s2length) {
-                        return;
-                }
-                result.deltaOffset = start;
-                if (start === s1length) {
-                        result.deltaText = s2.substring(start, s2length);
-                        result.deltaReplaceLength = 0;
-                        return;
-                } else if (start === s2length) {
-                        result.deltaText = '';
-                        result.deltaReplaceLength = s1length - start;
-                        return;
-                }
-                
-                var end1 = s1length - 1, end2 = s2length - 1;
-                while (end1 >= start && end2 >= start && s1.charCodeAt(end1) === s2.charCodeAt(end2)) {
-                        end1--;
-                        end2--;
-                }
-                result.deltaText = s2.substring(start, end2 + 1);
-                result.deltaReplaceLength = end1 - start + 1;
-        };
-        
-        /**
-         * Invoke all completion callbacks and clear the list afterwards.
-         */
-        UpdateService.prototype.onComplete = function(xhr, textStatus) {
-                var callbacks = this._completionCallbacks;
-                this._completionCallbacks = [];
-                for (var i = 0; i < callbacks.length; i++) {
-                        var callback = callbacks[i].callback;
-                        var params = callbacks[i].params;
-                        callback(params);
-                }
-        }
-        
-        /**
-         * Add a callback to be invoked when the service call has completed.
-         */
-        UpdateService.prototype.addCompletionCallback = function(callback, params) {
-                this._completionCallbacks.push({callback: callback, params: params});
-        }
-
-        UpdateService.prototype.invoke = function(editorContext, params, deferred) {
-                if (deferred === undefined) {
-                        deferred = jQuery.Deferred();
-                }
-                var knownServerState = editorContext.getServerState();
-                if (knownServerState.updateInProgress) {
-                        var self = this;
-                        this.addCompletionCallback(function() { self.invoke(editorContext, params, deferred) });
-                        return deferred.promise();
-                }
-                
-                var serverData = {
-                        contentType: params.contentType
-                };
-                var currentText = editorContext.getText();
-                if (params.sendFullText || knownServerState.text === undefined) {
-                        serverData.fullText = currentText;
-                } else {
-                        this.computeDelta(knownServerState.text, currentText, serverData);
-                        if (serverData.deltaText === undefined) {
-                                if (params.forceUpdate) {
-                                        serverData.deltaText = '';
-                                        serverData.deltaOffset = editorContext.getCaretOffset();
-                                        serverData.deltaReplaceLength = 0;
-                                } else {
-                                        deferred.resolve(knownServerState);
-                                        this.onComplete();
-                                        return deferred.promise();
-                                }
-                        }
-                        serverData.requiredStateId = knownServerState.stateId;
-                }
-
-                knownServerState.updateInProgress = true;
-                var self = this;
-                self.sendRequest(editorContext, {
-                        type: 'PUT',
-                        data: serverData,
-                        
-                        success: function(result) {
-                                if (result.conflict) {
-                                        // The server has lost its session state and the resource is loaded from the server
-                                        if (knownServerState.text !== undefined) {
-                                                delete knownServerState.updateInProgress;
-                                                delete knownServerState.text;
-                                                delete knownServerState.stateId;
-                                                self.invoke(editorContext, params, deferred);
-                                        } else {
-                                                deferred.reject(result.conflict);
-                                        }
-                                        return false;
-                                }
-                                var listeners = editorContext.updateServerState(currentText, result.stateId);
-                                for (var i = 0; i < listeners.length; i++) {
-                                        self.addCompletionCallback(listeners[i], params);
-                                }
-                                deferred.resolve(result);
-                        },
-                        
-                        error: function(xhr, textStatus, errorThrown) {
-                                if (xhr.status == 404 && !params.loadFromServer && knownServerState.text !== undefined) {
-                                        // The server has lost its session state and the resource is not loaded from the server
-                                        delete knownServerState.updateInProgress;
-                                        delete knownServerState.text;
-                                        delete knownServerState.stateId;
-                                        self.invoke(editorContext, params, deferred);
-                                        return true;
-                                }
-                                deferred.reject(errorThrown);
-                        },
-                        
-                        complete: self.onComplete.bind(self)
-                }, true);
-                return deferred.promise().always(function() {
-                        knownServerState.updateInProgress = false;
-                });
-        };
-        
-        return UpdateService;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/services/ValidationService.js b/language-web/src/main/js/xtext/services/ValidationService.js
deleted file mode 100644
index 85c9953d..00000000
--- a/language-web/src/main/js/xtext/services/ValidationService.js
+++ /dev/null
@@ -1,33 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['xtext/services/XtextService', 'jquery'], function(XtextService, jQuery) {
-        
-        /**
-         * Service class for validation.
-         */
-        function ValidationService(serviceUrl, resourceId) {
-                this.initialize(serviceUrl, 'validate', resourceId);
-        };
-        
-        ValidationService.prototype = new XtextService();
-        
-        ValidationService.prototype._checkPreconditions = function(editorContext, params) {
-                return this._state === undefined;
-        }
-
-        ValidationService.prototype._onConflict = function(editorContext, cause) {
-                this.setState(undefined);
-                return {
-                        suppressForcedUpdate: true
-                };
-        };
-        
-        return ValidationService;
-});
\ No newline at end of file
diff --git a/language-web/src/main/js/xtext/services/XtextService.js b/language-web/src/main/js/xtext/services/XtextService.js
deleted file mode 100644
index d3a4842f..00000000
--- a/language-web/src/main/js/xtext/services/XtextService.js
+++ /dev/null
@@ -1,280 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015, 2017 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-define(['jquery'], function(jQuery) {
-        
-        var globalState = {};
-        
-        /**
-         * Generic service implementation that can serve as superclass for specialized services.
-         */
-        function XtextService() {};
-
-        /**
-         * Initialize the request metadata for this service class. Two variants:
-         *  - initialize(serviceUrl, serviceType, resourceId, updateService)
-         *  - initialize(xtextServices, serviceType)
-         */
-        XtextService.prototype.initialize = function() {
-                this._serviceType = arguments[1];
-                if (typeof(arguments[0]) === 'string') {
-                        this._requestUrl = arguments[0] + '/' + this._serviceType;
-                        var resourceId = arguments[2];
-                        if (resourceId)
-                                this._encodedResourceId = encodeURIComponent(resourceId);
-                        this._updateService = arguments[3];
-                } else {
-                        var xtextServices = arguments[0];
-                        if (xtextServices.options) {
-                                this._requestUrl = xtextServices.options.serviceUrl + '/' + this._serviceType;
-                                var resourceId = xtextServices.options.resourceId;
-                                if (resourceId)
-                                        this._encodedResourceId = encodeURIComponent(resourceId);
-                        }
-                        this._updateService = xtextServices.updateService;
-                }
-        }
-        
-        XtextService.prototype.setState = function(state) {
-                this._state = state;
-        }
-        
-        /**
-         * Invoke the service with default service behavior.
-         */
-        XtextService.prototype.invoke = function(editorContext, params, deferred, callbacks) {
-                if (deferred === undefined) {
-                        deferred = jQuery.Deferred();
-                }
-                if (jQuery.isFunction(this._checkPreconditions) && !this._checkPreconditions(editorContext, params)) {
-                        deferred.reject();
-                        return deferred.promise();
-                }
-                var serverData = {
-                        contentType: params.contentType
-                };
-                var initResult;
-                if (jQuery.isFunction(this._initServerData))
-                        initResult = this._initServerData(serverData, editorContext, params);
-                var httpMethod = 'GET';
-                if (initResult && initResult.httpMethod)
-                        httpMethod = initResult.httpMethod;
-                var self = this;
-                if (!(initResult && initResult.suppressContent)) {
-                        if (params.sendFullText) {
-                                serverData.fullText = editorContext.getText();
-                                httpMethod = 'POST';
-                        } else {
-                                var knownServerState = editorContext.getServerState();
-                                if (knownServerState.updateInProgress) {
-                                        if (self._updateService) {
-                                                self._updateService.addCompletionCallback(function() {
-                                                        self.invoke(editorContext, params, deferred);
-                                                });
-                                        } else {
-                                                deferred.reject();
-                                        }
-                                        return deferred.promise();
-                                }
-                                if (knownServerState.stateId !== undefined) {
-                                        serverData.requiredStateId = knownServerState.stateId;
-                                }
-                        }
-                }
-                
-                var onSuccess;
-                if (jQuery.isFunction(this._getSuccessCallback)) {
-                        onSuccess = this._getSuccessCallback(editorContext, params, deferred);
-                } else {
-                        onSuccess = function(result) {
-                                if (result.conflict) {
-                                        if (self._increaseRecursionCount(editorContext)) {
-                                                var onConflictResult;
-                                                if (jQuery.isFunction(self._onConflict)) {
-                                                        onConflictResult = self._onConflict(editorContext, result.conflict);
-                                                }
-                                                if (!(onConflictResult && onConflictResult.suppressForcedUpdate) && !params.sendFullText
-                                                                && result.conflict == 'invalidStateId' && self._updateService) {
-                                                        self._updateService.addCompletionCallback(function() {
-                                                                self.invoke(editorContext, params, deferred);
-                                                        });
-                                                        var knownServerState = editorContext.getServerState();
-                                                        delete knownServerState.stateId;
-                                                        delete knownServerState.text;
-                                                        self._updateService.invoke(editorContext, params);
-                                                } else {
-                                                        self.invoke(editorContext, params, deferred);
-                                                }
-                                        } else {
-                                                deferred.reject();
-                                        }
-                                        return false;
-                                }
-                                if (jQuery.isFunction(self._processResult)) {
-                                        var processedResult = self._processResult(result, editorContext);
-                                        if (processedResult) {
-                                                deferred.resolve(processedResult);
-                                                return true;
-                                        }
-                                }
-                                deferred.resolve(result);
-                        };
-                }
-                
-                var onError = function(xhr, textStatus, errorThrown) {
-                        if (xhr.status == 404 && !params.loadFromServer && self._increaseRecursionCount(editorContext)) {
-                                var onConflictResult;
-                                if (jQuery.isFunction(self._onConflict)) {
-                                        onConflictResult = self._onConflict(editorContext, errorThrown);
-                                }
-                                var knownServerState = editorContext.getServerState();
-                                if (!(onConflictResult && onConflictResult.suppressForcedUpdate)
-                                                && knownServerState.text !== undefined && self._updateService) {
-                                        self._updateService.addCompletionCallback(function() {
-                                                self.invoke(editorContext, params, deferred);
-                                        });
-                                        delete knownServerState.stateId;
-                                        delete knownServerState.text;
-                                        self._updateService.invoke(editorContext, params);
-                                        return true;
-                                }
-                        }
-                        deferred.reject(errorThrown);
-                }
-                
-                self.sendRequest(editorContext, {
-                        type: httpMethod,
-                        data: serverData,
-                        success: onSuccess,
-                        error: onError
-                }, !params.sendFullText);
-                return deferred.promise().always(function() {
-                        self._recursionCount = undefined;
-                });
-        }
-
-        /**
-         * Send an HTTP request to invoke the service.
-         */
-        XtextService.prototype.sendRequest = function(editorContext, settings, needsSession) {
-                var self = this;
-                self.setState('started');
-                var corsEnabled = editorContext.xtextServices.options['enableCors'];
-                if(corsEnabled) {
-                        settings.crossDomain = true;
-                        settings.xhrFields = {withCredentials: true};
-                } 
-                var onSuccess = settings.success;
-                settings.success = function(result) {
-                        var accepted = true;
-                        if (jQuery.isFunction(onSuccess)) {
-                                accepted = onSuccess(result);
-                        }
-                        if (accepted || accepted === undefined) {
-                                self.setState('finished');
-                                if (editorContext.xtextServices) {
-                                        var successListeners = editorContext.xtextServices.successListeners;
-                                        if (successListeners) {
-                                                for (var i = 0; i < successListeners.length; i++) {
-                                                        var listener = successListeners[i];
-                                                        if (jQuery.isFunction(listener)) {
-                                                                listener(self._serviceType, result);
-                                                        }
-                                                }
-                                        }
-                                }
-                        }
-                };
-                
-                var onError = settings.error;
-                settings.error = function(xhr, textStatus, errorThrown) {
-                        var resolved = false;
-                        if (jQuery.isFunction(onError)) {
-                                resolved = onError(xhr, textStatus, errorThrown);
-                        }
-                        if (!resolved) {
-                                self.setState(undefined);
-                                self._reportError(editorContext, textStatus, errorThrown, xhr);
-                        }
-                };
-                
-                settings.async = true;
-                var requestUrl = self._requestUrl;
-                if (!settings.data.resource && self._encodedResourceId) {
-                        if (requestUrl.indexOf('?') >= 0)
-                                requestUrl += '&resource=' + self._encodedResourceId;
-                        else
-                                requestUrl += '?resource=' + self._encodedResourceId;
-                }
-                
-                if (needsSession && globalState._initPending) {
-                        // We have to wait until the initial request has finished to make sure the client has
-                        // received a valid session id
-                        if (!globalState._waitingRequests)
-                                globalState._waitingRequests = [];
-                        globalState._waitingRequests.push({requestUrl: requestUrl, settings: settings});
-                } else {
-                        if (needsSession && !globalState._initDone) {
-                                globalState._initPending = true;
-                                var onComplete = settings.complete;
-                                settings.complete = function(xhr, textStatus) {
-                                        if (jQuery.isFunction(onComplete)) {
-                                                onComplete(xhr, textStatus);
-                                        }
-                                        delete globalState._initPending;
-                                        globalState._initDone = true;
-                                        if (globalState._waitingRequests) {
-                                                for (var i = 0; i < globalState._waitingRequests.length; i++) {
-                                                        var request = globalState._waitingRequests[i];
-                                                        jQuery.ajax(request.requestUrl, request.settings);
-                                                }
-                                                delete globalState._waitingRequests;
-                                        }
-                                }
-                        }
-                        jQuery.ajax(requestUrl, settings);
-                }
-        }
-        
-        /**
-         * Use this in case of a conflict before retrying the service invocation. If the number
-         * of retries exceeds the limit, an error is reported and the function returns false.
-         */
-        XtextService.prototype._increaseRecursionCount = function(editorContext) {
-                if (this._recursionCount === undefined)
-                        this._recursionCount = 1;
-                else
-                        this._recursionCount++;
-
-                if (this._recursionCount >= 10) {
-                        this._reportError(editorContext, 'warning', 'Xtext service request failed after 10 attempts.', {});
-                        return false;
-                }
-                return true;
-        },
-        
-        /**
-         * Report an error to the listeners.
-         */
-        XtextService.prototype._reportError = function(editorContext, severity, message, requestData) {
-                if (editorContext.xtextServices) {
-                        var errorListeners = editorContext.xtextServices.errorListeners;
-                        if (errorListeners) {
-                                for (var i = 0; i < errorListeners.length; i++) {
-                                        var listener = errorListeners[i];
-                                        if (jQuery.isFunction(listener)) {
-                                                listener(this._serviceType, severity, message, requestData);
-                                        }
-                                }
-                        }
-                }
-        }
-        
-        return XtextService;
-});
diff --git a/language-web/src/main/js/xtext/xtext-codemirror.d.ts b/language-web/src/main/js/xtext/xtext-codemirror.d.ts
deleted file mode 100644
index fff850b8..00000000
--- a/language-web/src/main/js/xtext/xtext-codemirror.d.ts
+++ /dev/null
@@ -1,43 +0,0 @@
-import { Editor } from 'codemirror';
-
-export function createEditor(options: IXtextOptions): IXtextCodeMirrorEditor;
-
-export function createServices(editor: Editor, options: IXtextOptions): IXtextServices;
-
-export function removeServices(editor: Editor): void;
-
-export interface IXtextOptions {
-  baseUrl?: string;
-  contentType?: string;
-  dirtyElement?: string | Element;
-  dirtyStatusClass?: string;
-  document?: Document;
-  enableContentAssistService?: boolean;
-  enableCors?: boolean;
-  enableFormattingAction?: boolean;
-  enableFormattingService?: boolean;
-  enableGeneratorService?: boolean;
-  enableHighlightingService?: boolean;
-  enableOccurrencesService?: boolean;
-  enableSaveAction?: boolean;
-  enableValidationService?: boolean;
-  loadFromServer?: boolean;
-  mode?: string;
-  parent?: string | Element;
-  parentClass?: string;
-  resourceId?: string;
-  selectionUpdateDelay?: number;
-  sendFullText?: boolean;
-  serviceUrl?: string;
-  showErrorDialogs?: boolean;
-  syntaxDefinition?: string;
-  textUpdateDelay?: number;
-  xtextLang?: string;
-}
-
-export interface IXtextCodeMirrorEditor extends Editor {
-  xtextServices: IXtextServices;
-}
-
-export interface IXtextServices {
-}
diff --git a/language-web/src/main/js/xtext/xtext-codemirror.js b/language-web/src/main/js/xtext/xtext-codemirror.js
deleted file mode 100644
index d246172a..00000000
--- a/language-web/src/main/js/xtext/xtext-codemirror.js
+++ /dev/null
@@ -1,473 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2015, 2017 itemis AG (http://www.itemis.eu) and others.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License 2.0 which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * SPDX-License-Identifier: EPL-2.0
- *******************************************************************************/
-
-/*
- * Use `createEditor(options)` to create an Xtext editor. You can specify options either
- * through the function parameter or through `data-editor-x` attributes, where x is an
- * option name with camelCase converted to hyphen-separated.
- * In addition to the options supported by CodeMirror (https://codemirror.net/doc/manual.html#config),
- * the following options are available:
- *
- * baseUrl = "/" {String}
- *     The path segment where the Xtext service is found; see serviceUrl option.
- * contentType {String}
- *     The content type included in requests to the Xtext server.
- * dirtyElement {String | DOMElement}
- *     An element into which the dirty status class is written when the editor is marked dirty;
- *     it can be either a DOM element or an ID for a DOM element.
- * dirtyStatusClass = 'dirty' {String}
- *     A CSS class name written into the dirtyElement when the editor is marked dirty.
- * document {Document}
- *     The document; if not specified, the global document is used.
- * enableContentAssistService = true {Boolean}
- *     Whether content assist should be enabled.
- * enableCors = true {Boolean}
- *     Whether CORS should be enabled for service request.
- * enableFormattingAction = false {Boolean}
- *     Whether the formatting action should be bound to the standard keystroke ctrl+shift+s / cmd+shift+f.
- * enableFormattingService = true {Boolean}
- *     Whether text formatting should be enabled.
- * enableGeneratorService = true {Boolean}
- *     Whether code generation should be enabled (must be triggered through JavaScript code).
- * enableHighlightingService = true {Boolean}
- *     Whether semantic highlighting (computed on the server) should be enabled.
- * enableOccurrencesService = true {Boolean}
- *     Whether marking occurrences should be enabled.
- * enableSaveAction = false {Boolean}
- *     Whether the save action should be bound to the standard keystroke ctrl+s / cmd+s.
- * enableValidationService = true {Boolean}
- *     Whether validation should be enabled.
- * loadFromServer = true {Boolean}
- *     Whether to load the editor content from the server.
- * mode {String}
- *     The name of the syntax highlighting mode to use; the mode has to be registered externally
- *     (see CodeMirror documentation).
- * parent = 'xtext-editor' {String | DOMElement}
- *     The parent element for the view; it can be either a DOM element or an ID for a DOM element.
- * parentClass = 'xtext-editor' {String}
- *     If the 'parent' option is not given, this option is used to find elements that match the given class name.
- * resourceId {String}
- *     The identifier of the resource displayed in the text editor; this option is sent to the server to
- *     communicate required information on the respective resource.
- * selectionUpdateDelay = 550 {Number}
- *     The number of milliseconds to wait after a selection change before Xtext services are invoked.
- * sendFullText = false {Boolean}
- *     Whether the full text shall be sent to the server with each request; use this if you want
- *     the server to run in stateless mode. If the option is inactive, the server state is updated regularly.
- * serviceUrl {String}
- *     The URL of the Xtext servlet; if no value is given, it is constructed using the baseUrl option in the form
- *     {location.protocol}//{location.host}{baseUrl}xtext-service
- * showErrorDialogs = false {Boolean}
- *     Whether errors should be displayed in popup dialogs.
- * syntaxDefinition {String}
- *     If the 'mode' option is not set, the default mode 'xtext/{xtextLang}' is used. Set this option to
- *     'none' to suppress this behavior and disable syntax highlighting.
- * textUpdateDelay = 500 {Number}
- *     The number of milliseconds to wait after a text change before Xtext services are invoked.
- * xtextLang {String}
- *     The language name (usually the file extension configured for the language).
- */
-define([
-    'jquery',
-    'codemirror',
-    'codemirror/addon/hint/show-hint',
-    'xtext/compatibility',
-    'xtext/ServiceBuilder',
-        'xtext/CodeMirrorEditorContext',
-        'codemirror/mode/javascript/javascript'
-], function(jQuery, CodeMirror, ShowHint, compatibility, ServiceBuilder, EditorContext) {
-        
-        var exports = {};
-        
-        /**
-         * Create one or more Xtext editor instances configured with the given options.
-         * The return value is either a CodeMirror editor or an array of CodeMirror editors.
-         */
-        exports.createEditor = function(options) {
-                if (!options)
-                        options = {};
-                
-                var query;
-                if (jQuery.type(options.parent) === 'string') {
-                        query = jQuery('#' + options.parent, options.document);
-                } else if (options.parent) {
-                        query = jQuery(options.parent);
-                } else if (jQuery.type(options.parentClass) === 'string') {
-                        query = jQuery('.' + options.parentClass, options.document);
-                } else {
-                        query = jQuery('#xtext-editor', options.document);
-                        if (query.length == 0)
-                                query = jQuery('.xtext-editor', options.document);
-                }
-                
-                var editors = [];
-                query.each(function(index, parent) {
-                        var editorOptions = ServiceBuilder.mergeParentOptions(parent, options);
-                        if (!editorOptions.value)
-                                editorOptions.value = jQuery(parent).text();
-                        var editor = CodeMirror(function(element) {
-                                jQuery(parent).empty().append(element);
-                        }, editorOptions);
-                        
-                        exports.createServices(editor, editorOptions);
-                        editors[index] = editor;
-                });
-                
-                if (editors.length == 1)
-                        return editors[0];
-                else
-                        return editors;
-        }
-        
-        function CodeMirrorServiceBuilder(editor, xtextServices) {
-                this.editor = editor;
-                xtextServices.editorContext._highlightingMarkers = [];
-                xtextServices.editorContext._validationMarkers = [];
-                xtextServices.editorContext._occurrenceMarkers = [];
-                ServiceBuilder.call(this, xtextServices);
-        }
-        CodeMirrorServiceBuilder.prototype = new ServiceBuilder();
-                
-        /**
-         * Configure Xtext services for the given editor. The editor does not have to be created
-         * with createEditor(options).
-         */
-        exports.createServices = function(editor, options) {
-                if (options.enableValidationService || options.enableValidationService === undefined) {
-                        editor.setOption('gutters', ['annotations-gutter']);
-                }
-                var xtextServices = {
-                        options: options,
-                        editorContext: new EditorContext(editor)
-                };
-                var serviceBuilder = new CodeMirrorServiceBuilder(editor, xtextServices);
-                serviceBuilder.createServices();
-                xtextServices.serviceBuilder = serviceBuilder;
-                editor.xtextServices = xtextServices;
-                return xtextServices;
-        }
-        
-        /**
-         * Remove all services and listeners that have been previously created with createServices(editor, options).
-         */
-        exports.removeServices = function(editor) {
-                if (!editor.xtextServices)
-                        return;
-                var services = editor.xtextServices;
-                if (services.modelChangeListener)
-                        editor.off('changes', services.modelChangeListener);
-                if (services.cursorActivityListener)
-                        editor.off('cursorActivity', services.cursorActivityListener);
-                if (services.saveKeyMap)
-                        editor.removeKeyMap(services.saveKeyMap);
-                if (services.contentAssistKeyMap)
-                        editor.removeKeyMap(services.contentAssistKeyMap);
-                if (services.formatKeyMap)
-                        editor.removeKeyMap(services.formatKeyMap);
-                var editorContext = services.editorContext;
-                var highlightingMarkers = editorContext._highlightingMarkers;
-                if (highlightingMarkers) {
-                        for (var i = 0; i < highlightingMarkers.length; i++) {
-                                highlightingMarkers[i].clear();
-                        }
-                }
-                if (editorContext._validationAnnotations)
-                        services.serviceBuilder._clearAnnotations(editorContext._validationAnnotations);
-                var validationMarkers = editorContext._validationMarkers;
-                if (validationMarkers) {
-                        for (var i = 0; i < validationMarkers.length; i++) {
-                                validationMarkers[i].clear();
-                        }
-                }
-                var occurrenceMarkers = editorContext._occurrenceMarkers;
-                if (occurrenceMarkers) {
-                        for (var i = 0; i < occurrenceMarkers.length; i++)  {
-                                occurrenceMarkers[i].clear();
-                        }
-                }
-                delete editor.xtextServices;
-        }
-        
-        /**
-         * Syntax highlighting (without semantic highlighting).
-         */
-        CodeMirrorServiceBuilder.prototype.setupSyntaxHighlighting = function() {
-                var options = this.services.options;
-                // If the mode option is set, syntax highlighting has already been configured by CM
-                if (!options.mode && options.syntaxDefinition != 'none' && options.xtextLang) {
-                        this.editor.setOption('mode', 'xtext/' + options.xtextLang);
-                }
-        }
-                
-        /**
-         * Document update service.
-         */
-        CodeMirrorServiceBuilder.prototype.setupUpdateService = function(refreshDocument) {
-                var services = this.services;
-                var editorContext = services.editorContext;
-                var textUpdateDelay = services.options.textUpdateDelay;
-                if (!textUpdateDelay)
-                        textUpdateDelay = 500;
-                services.modelChangeListener = function(event) {
-                        if (!event._xtext_init)
-                                editorContext.setDirty(true);
-                        if (editorContext._modelChangeTimeout)
-                                clearTimeout(editorContext._modelChangeTimeout);
-                        editorContext._modelChangeTimeout = setTimeout(function() {
-                                if (services.options.sendFullText)
-                                        refreshDocument();
-                                else
-                                        services.update();
-                        }, textUpdateDelay);
-                }
-                if (!services.options.resourceId || !services.options.loadFromServer)
-                        services.modelChangeListener({_xtext_init: true});
-                this.editor.on('changes', services.modelChangeListener);
-        }
-        
-        /**
-         * Persistence services: load, save, and revert.
-         */
-        CodeMirrorServiceBuilder.prototype.setupPersistenceServices = function() {
-                var services = this.services;
-                if (services.options.enableSaveAction) {
-                        var userAgent = navigator.userAgent.toLowerCase();
-                        var saveFunction = function(editor) {
-                                services.saveResource();
-                        };
-                        services.saveKeyMap = /mac os/.test(userAgent) ? {'Cmd-S': saveFunction}: {'Ctrl-S': saveFunction};
-                        this.editor.addKeyMap(services.saveKeyMap);
-                }
-        }
-                
-        /**
-         * Content assist service.
-         */
-        CodeMirrorServiceBuilder.prototype.setupContentAssistService = function() {
-                var services = this.services;
-                var editorContext = services.editorContext;
-                services.contentAssistKeyMap = {'Ctrl-Space': function(editor) {
-                        var params = ServiceBuilder.copy(services.options);
-                        var cursor = editor.getCursor();
-                        params.offset = editor.indexFromPos(cursor);
-                        services.contentAssistService.invoke(editorContext, params).done(function(entries) {
-                                editor.showHint({hint: function(editor, options) {
-                                        return {
-                                                list: entries.map(function(entry) {
-                                                        var displayText;
-                                                        if (entry.label)
-                                                                displayText = entry.label;
-                                                        else
-                                                                displayText = entry.proposal;
-                                                        if (entry.description)
-                                                                displayText += ' (' + entry.description + ')';
-                                                        var prefixLength = 0
-                                                        if (entry.prefix)
-                                                                prefixLength = entry.prefix.length
-                                                return {
-                                                        text: entry.proposal,
-                                                        displayText: displayText,
-                                                        from: {
-                                                                line: cursor.line,
-                                                                ch: cursor.ch - prefixLength
-                                                        }
-                                                };
-                                                }),
-            from: cursor,
-                                                to: cursor
-                                        };
-                                }});
-                        });
-                }};
-                this.editor.addKeyMap(services.contentAssistKeyMap);
-        }
-                
-        /**
-         * Semantic highlighting service.
-         */
-        CodeMirrorServiceBuilder.prototype.doHighlighting = function() {
-                var services = this.services;
-                var editorContext = services.editorContext;
-                var editor = this.editor;
-                services.computeHighlighting().always(function() {
-                        var highlightingMarkers = editorContext._highlightingMarkers;
-                        if (highlightingMarkers) {
-                                for (var i = 0; i < highlightingMarkers.length; i++) {
-                                        highlightingMarkers[i].clear();
-                                }
-                        }
-                        editorContext._highlightingMarkers = [];
-                }).done(function(result) {
-                        for (var i = 0; i < result.regions.length; ++i) {
-                                var region = result.regions[i];
-                                var from = editor.posFromIndex(region.offset);
-                                var to = editor.posFromIndex(region.offset + region.length);
-                                region.styleClasses.forEach(function(styleClass) {
-                                        var marker =  editor.markText(from, to, {className: styleClass});
-                                        editorContext._highlightingMarkers.push(marker);
-                                });
-                        }
-                });
-        }
-        
-        var annotationWeight = {
-                error: 30,
-                warning: 20,
-                info: 10
-        };
-        CodeMirrorServiceBuilder.prototype._getAnnotationWeight = function(annotation) {
-                if (annotationWeight[annotation] !== undefined)
-                        return annotationWeight[annotation];
-                else
-                        return 0;
-        }
-        
-        CodeMirrorServiceBuilder.prototype._clearAnnotations = function(annotations) {
-                var editor = this.editor;
-    editor.clearGutter('annotations-gutter');
-                for (var i = 0; i < annotations.length; i++) {
-                        var annotation = annotations[i];
-                        if (annotation) {
-                                annotations[i] = undefined;
-                        }
-                }
-        }
-        
-        CodeMirrorServiceBuilder.prototype._refreshAnnotations = function(annotations) {
-                var editor = this.editor;
-                for (var i = 0; i < annotations.length; i++) {
-                        var annotation = annotations[i];
-                        if (annotation) {
-                                var classProp = ' class="xtext-annotation_' + annotation.type + '"';
-                                var titleProp = annotation.description ? ' title="' + annotation.description.replace(/"/g, '&quot;') + '"' : '';
-                                var element = jQuery('<div' + classProp + titleProp + '></div>').get(0);
-                                editor.setGutterMarker(i, 'annotations-gutter', element);
-                        }
-                }
-        }
-        
-        /**
-         * Validation service.
-         */
-        CodeMirrorServiceBuilder.prototype.doValidation = function() {
-                var services = this.services;
-                var editorContext = services.editorContext;
-                var editor = this.editor;
-                var self = this;
-                services.validate().always(function() {
-                        if (editorContext._validationAnnotations)
-                                self._clearAnnotations(editorContext._validationAnnotations);
-                        else
-                                editorContext._validationAnnotations = [];
-                        var validationMarkers = editorContext._validationMarkers;
-                        if (validationMarkers) {
-                                for (var i = 0; i < validationMarkers.length; i++) {
-                                        validationMarkers[i].clear();
-                                }
-                        }
-                        editorContext._validationMarkers = [];
-                }).done(function(result) {
-                        var validationAnnotations = editorContext._validationAnnotations;
-                        for (var i = 0; i < result.issues.length; i++) {
-                                var entry = result.issues[i];
-                                var annotation = validationAnnotations[entry.line - 1];
-                                var weight = self._getAnnotationWeight(entry.severity);
-                                if (annotation) {
-                                        if (annotation.weight < weight) {
-                                                annotation.type = entry.severity;
-                                                annotation.weight = weight;
-                                        }
-                                        if (annotation.description)
-                                                annotation.description += '\n' + entry.description;
-                                        else
-                                                annotation.description = entry.description;
-                                } else {
-                                        validationAnnotations[entry.line - 1] = {
-                                                type: entry.severity,
-                                                weight: weight,
-                                                description: entry.description
-                                        };
-                                }
-                                var from = editor.posFromIndex(entry.offset);
-                                var to = editor.posFromIndex(entry.offset + entry.length);
-                                var marker =  editor.markText(from, to, {
-                                        className: 'xtext-marker_' + entry.severity,
-                                        title: entry.description
-                                });
-                                editorContext._validationMarkers.push(marker);
-                        }
-                        self._refreshAnnotations(validationAnnotations);
-                });
-        }
-                
-        /**
-         * Occurrences service.
-         */
-        CodeMirrorServiceBuilder.prototype.setupOccurrencesService = function() {
-                var services = this.services;
-                var editorContext = services.editorContext;
-                var selectionUpdateDelay = services.options.selectionUpdateDelay;
-                if (!selectionUpdateDelay)
-                        selectionUpdateDelay = 550;
-                var editor = this.editor;
-                var self = this;
-                services.cursorActivityListener = function() {
-                        if (editorContext._selectionChangeTimeout) {
-                                clearTimeout(editorContext._selectionChangeTimeout);
-                        }
-                        editorContext._selectionChangeTimeout = setTimeout(function() {
-                                var params = ServiceBuilder.copy(services.options);
-                                var cursor = editor.getCursor();
-                                params.offset = editor.indexFromPos(cursor);
-                                services.occurrencesService.invoke(editorContext, params).always(function() {
-                                        var occurrenceMarkers = editorContext._occurrenceMarkers;
-                                        if (occurrenceMarkers) {
-                                                for (var i = 0; i < occurrenceMarkers.length; i++)  {
-                                                        occurrenceMarkers[i].clear();
-                                                }
-                                        }
-                                        editorContext._occurrenceMarkers = [];
-                                }).done(function(occurrencesResult) {
-                                        for (var i = 0; i < occurrencesResult.readRegions.length; i++) {
-                                                var region = occurrencesResult.readRegions[i];
-                                                var from = editor.posFromIndex(region.offset);
-                                                var to = editor.posFromIndex(region.offset + region.length);
-                                                var marker =  editor.markText(from, to, {className: 'xtext-marker_read'});
-                                                editorContext._occurrenceMarkers.push(marker);
-                                        }
-                                        for (var i = 0; i < occurrencesResult.writeRegions.length; i++) {
-                                                var region = occurrencesResult.writeRegions[i];
-                                                var from = editor.posFromIndex(region.offset);
-                                                var to = editor.posFromIndex(region.offset + region.length);
-                                                var marker =  editor.markText(from, to, {className: 'xtext-marker_write'});
-                                                editorContext._occurrenceMarkers.push(marker);
-                                        }
-                                });
-                        }, selectionUpdateDelay);
-                }
-                editor.on('cursorActivity', services.cursorActivityListener);
-        }
-                
-        /**
-         * Formatting service.
-         */
-        CodeMirrorServiceBuilder.prototype.setupFormattingService = function() {
-                var services = this.services;
-                if (services.options.enableFormattingAction) {
-                        var userAgent = navigator.userAgent.toLowerCase();
-                        var formatFunction = function(editor) {
-                                services.format();
-                        };
-                        services.formatKeyMap = /mac os/.test(userAgent) ? {'Shift-Cmd-F': formatFunction}: {'Shift-Ctrl-S': formatFunction};
-                        this.editor.addKeyMap(services.formatKeyMap);
-                }
-        }
-        
-        return exports;
-});
diff --git a/language-web/src/main/js/editor/xtextMessages.ts b/language-web/src/main/js/xtext/xtextMessages.ts
index 68737958..68737958 100644
--- a/language-web/src/main/js/editor/xtextMessages.ts
+++ b/language-web/src/main/js/xtext/xtextMessages.ts
diff --git a/language-web/src/main/js/editor/xtextServiceResults.ts b/language-web/src/main/js/xtext/xtextServiceResults.ts
index 6c3d9daf..6c3d9daf 100644
--- a/language-web/src/main/js/editor/xtextServiceResults.ts
+++ b/language-web/src/main/js/xtext/xtextServiceResults.ts
diff --git a/language-web/tsconfig.json b/language-web/tsconfig.json
index d028a64f..f1f24a1f 100644
--- a/language-web/tsconfig.json
+++ b/language-web/tsconfig.json
@@ -3,9 +3,6 @@
     "target": "ES2020",
     "module": "ES2020",
     "moduleResolution": "node",
-    "paths": {
-      "xtext/*": ["./src/main/js/xtext/*"],
-    },
     "esModuleInterop": true,
     "allowSyntheticDefaultImports": true,
     "jsx": "react",
diff --git a/language-web/tsconfig.sonar.json b/language-web/tsconfig.sonar.json
index 1cc74f23..ea3ecc19 100644
--- a/language-web/tsconfig.sonar.json
+++ b/language-web/tsconfig.sonar.json
@@ -3,9 +3,6 @@
     "target": "ES2020",
     "module": "ES2020",
     "moduleResolution": "node",
-    "paths": {
-      "xtext/*": ["./src/main/js/xtext/*"]
-    },
     "esModuleInterop": true,
     "allowSyntheticDefaultImports": true,
     "jsx": "react",
diff --git a/language-web/webpack.config.js b/language-web/webpack.config.js
index 6714fa6b..801a705c 100644
--- a/language-web/webpack.config.js
+++ b/language-web/webpack.config.js
@@ -28,7 +28,6 @@ const resolveSources = sources => path.resolve(__dirname, 'src', sources);
 const mainJsSources = resolveSources('main/js');
 const babelLoaderFilters = {
   include: [mainJsSources],
-  exclude: [resolveSources('main/js/xtext')],
 };
 const babelPresets = [
   [
@@ -151,9 +150,6 @@ module.exports = {
       mainJsSources,
     ],
     extensions: ['.js', '.jsx', '.ts', '.tsx'],
-    alias: {
-      images: resolveSources('main/images'),
-    },
   },
   devtool: devMode ? 'inline-source-map' : 'source-map',
   optimization: {